import numpy as np
import cv2
import glob


def save_calibration():
    # termination criteria
    criteria = (cv2.TERM_CRITERIA_EPS + cv2.TERM_CRITERIA_MAX_ITER, 30, 0.001)

    # prepare object points, like (0,0,0), (1,0,0), (2,0,0) ....,(6,5,0)
    objp = np.zeros((6 * 9, 3), np.float32)
    objp[:, :2] = np.mgrid[0:9, 0:6].T.reshape(-1, 2)

    # Arrays to store object points and image points from all the images.
    objpoints = []  # 3d point in real world space
    imgpoints = []  # 2d points in image plane.

    images = glob.glob('capture/cam1/*.jpg')
    # count = 0
    for fname in images:
        img = cv2.imread(fname)
        gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

        # Find the chess board corners
        ret, corners = cv2.findChessboardCorners(gray, (9, 6), None)

        # If found, add object points, image points (after refining them)
        if ret == True:
            objpoints.append(objp)

            corners2 = cv2.cornerSubPix(gray, corners, (11, 11), (-1, -1), criteria)
            imgpoints.append(corners2)

            # Draw and display the corners
            img = cv2.drawChessboardCorners(img, (9, 6), corners, ret)

            # count = count + 1
            # name = str(count)
            cv2.imshow('img', img)
            cv2.waitKey(500)
            # filename = str(count) + '.jpg'
            # cv2.imwrite(filename, img)

    cv2.destroyAllWindows()

    ret, mtx, dist, rvecs, tvecs = cv2.calibrateCamera(objpoints, imgpoints, gray.shape[::-1], None, None)
    print(mtx)
    print(dist)
    print(rvecs)
    print(tvecs)

    np.savez('calibration_cam1.npz',
             objpoints=objpoints,
             imgpoints=imgpoints,
             ret=ret,
             mtx=mtx,
             dist=dist,
             rvecs=rvecs,
             tvecs=tvecs)
    print('Camera calibration saved successfully!')


save_calibration()
